Safety aspects of long-term nitrendipine therapy.

More than 1,700 patients with essential or renal hypertension were treated with nitrendipine; data from 967 of these were included in a data pool, and safety data were evaluated. Treatment duration was between 7 days and 2 years. The most frequent side-effects were headache, flush, oedema, dizziness, and palpitations due to the pharmacodynamic effect of the drug. All other side-effects had an incidence below 2%. Eighty-two of the 967 patients stopped therapy before the end of the trial. In 33 of these patients, this was probably due to the side-effects of nitrendipine. Hematological and clinical chemistry data did not indicate any systemic or organ damage. When nitrendipine was combined with thiazides, a lowering of plasma potassium levels could be found, which, however, did not necessitate any therapy.